With elevated ferritin, a normal complete blood count, and normal serum iron, what work‑up is indicated?

Work-Up for Elevated Ferritin with Normal CBC and Iron Studies

When ferritin is elevated but CBC and serum iron are normal, you must first systematically exclude common non-iron overload causes before pursuing genetic testing for hemochromatosis. This approach is critical because over 90% of hyperferritinemia cases are not due to iron overload 1.

Initial Evaluation: Rule Out Common Causes

Before ordering any genetic tests, check transferrin saturation (TS) – this is the key discriminator between true iron overload and other causes of hyperferritinemia 2.

Step 1: Measure Transferrin Saturation

• If TS ≥45%: Proceed to HFE genetic testing for hemochromatosis 2
• If TS <45%: Iron overload is unlikely; investigate alternative causes 1

Step 2: Screen for Non-Iron Overload Causes

In over 90% of outpatients with hyperferritinemia, one of the following is responsible 1:

Inflammatory/Infectious Conditions:

• Check C-reactive protein (CRP) for inflammation 1
• Ferritin is an acute-phase reactant and rises with chronic inflammatory conditions, malignancy, and lymphomas 2

Hepatocellular Injury:

• Check AST, ALT, and CK for cell necrosis 1
• Evaluate for alcoholic liver disease, chronic hepatitis B/C, and non-alcoholic fatty liver disease (NAFLD) 2

Metabolic Syndrome:

• Assess blood pressure, BMI, cholesterol, triglycerides, and serum glucose 1
• NAFLD and metabolic syndrome are common causes of hyperferritinemia 2

Alcohol Consumption:

• Document chronic alcohol intake, which commonly elevates ferritin 1

Malignancy:

• Consider ESR and CT scan if clinically indicated 1
• Markedly elevated ferritin (>1000 μg/L) is frequently associated with malignancy, particularly acute leukemia, lymphoma, hepatoma, and pancreatic cancer 3

When to Pursue Hemochromatosis Work-Up

Only proceed with HFE genetic testing if transferrin saturation is elevated (≥45%) in addition to elevated ferritin 1. The combination of both abnormalities is required to justify genetic testing 2.

HFE Genetic Testing

• Test for C282Y and H63D mutations 1
• Critical caveat: Diagnosis of HFE hemochromatosis requires BOTH genetic confirmation AND evidence of increased iron stores – genotype alone is insufficient 1

Additional Testing for Confirmed Hemochromatosis

If C282Y homozygous with elevated ferritin:

• Liver biopsy is generally NOT needed for diagnosis 1
• Consider liver biopsy only if 1, 4:
  • Ferritin >1000 μg/L
  • Elevated AST or ALT
  • Hepatomegaly present
  • Age >40 years
  • These factors predict cirrhosis risk

MRI for iron quantification:

• Can quantify hepatic iron concentration non-invasively 4
• Useful when diagnosis is unclear or to assess extrahepatic organ involvement 4
• Not required for straightforward C282Y homozygotes but helps predict phlebotomy requirements 4

Special Populations

In inflammatory conditions (IBD, CHF, CKD):

• Standard ferritin thresholds don't apply because ferritin rises as an acute-phase reactant 5
• Use higher thresholds: ferritin <100 μg/L or TS <20% indicates iron deficiency in these patients 5
• If ferritin is 100-300 μg/L, TS <20% is required to confirm iron deficiency 5

When to Refer

Refer to gastroenterology, hematology, or iron overload specialist if 6:

• Ferritin >1000 μg/L
• Cause of elevated ferritin remains unclear after initial work-up
• Confirmed hemochromatosis requiring therapeutic phlebotomy

Key Pitfalls to Avoid

• Never assume elevated ferritin equals iron overload – it's usually inflammation, liver disease, or metabolic syndrome 2
• Don't order HFE testing without checking transferrin saturation first – this wastes resources and creates unnecessary anxiety 1
• Don't diagnose hemochromatosis based on genetics alone – you need evidence of actual iron accumulation 1
• Remember that normal serum iron doesn't rule out iron overload – transferrin saturation is the critical test 2